Services
Paternity Testing
DNA profiling is used to resolve disputed cases of paternity. This method uses the innovative Polymerase Chain Reaction (PCR) technique to amplify a small amount of DNA followed by analysis of short tandem repeats (STR’s - are repeated DNA sequences at designated DNA loci).
A commercial kit is used for STR analysis and identifies STR’s at 15 different DNA loci. Every person inherits an allele (marker) from each parent. Should a marker be present in the DNA of the child that is not present in the DNA profile of the ‘alleged’ father, then he can be ‘excluded’ at that locus. International standards are followed which prescribe that a man can only be excluded as the biological father of a child if he has been excluded at a minimum of 3 different STR loci.
There are many advantages to this type of technology:
- Only a small amount of blood is needed for testing; a finger prick from an adult or a finger / heel prick from a child depending on the age.
- Samples are stored indefinitely at room temperature
- A once off test will give accurate, reliable and reproducible results
- Probability of paternity is greater than 99.9%
This kind of technology is currently the most advanced available and is in use worldwide for human identification.
Contact details
Area 1 (Johannesburg)
Tissue Immunology + Paternity Laboratory
011 761 9227
Area 2 (Durban)
Tissue Immunology + Paternity Laboratory
031 719 6619
Platelets play an integral part in a number of clinical conditions, the most commonly seen being Neonatal Alloimmune Thrombocytopenia (NAIT) and Platelet refractoriness (PR).
NAIT is the platelet equivalent of HDN, where maternal antibodies are responsible for the destruction of fetal cells. In cases of NAIT, the maternal platelet antibody crosses the placental barrier into the fetal circulation and destroys the fetal platelets. The low platelet count is responsible for bleeding episodes in the fetus and can lead to intercranial hemorrhage (ICH) which can be life threatening and have serious neurological consequences for the infant.
Detection of antibodies to platelet antigens, HPA 1, 3, 4 and 5 is performed on mother’s serum in cases of suspected NAIT. If antibodies are detected, genotyping can be performed for platelet antigens HPA 1-5 and -15 to confirm antibody status. Should the baby require a matched platelet transfusion, a donor can be obtained from the HPA –typed donor database available. The most commonly found antibodies causing NAIT in Caucasians are HPA 1a and HPA 5b.
In cases where patients are not responding to platelet transfusions, HLA or HPA antibodies, or both, may be suspected. The patient is tested for HPA and HLA antibodies, and then HPA and HLA typed.
There are HPA and HLA - typed donor databases available.
In suspected cases of Auto-immune Thrombocytopenia, patients and also be tested for platelet auto antibodies. The diagnosis of this disease is one of exclusion, and the results obtained by this test cannot be used as the only supporting evidence for a positive diagnosis.
Contact details
Area 1
Dr Zyta Foxcroft, Senior Biomedical Scientist Tissue Immunology
011 761 9214
Area 1 (Johannesburg)
Tissue Immunology + Paternity Laboratory
011 761 9227
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